Morfologia e efeitos do ataque de Metaxyonycha angusta (Perty) (Col.: Chrysomelidae) sobre o crescimento e produção de eucalipto

• Autor(a) principal: Fernandes, Laine Cristina
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/875
• topic: Besouro-quatro-pintas; Impacto; Biologia; Eucalipto; Four-spotted-beetle; Impact; Biology; Eucalypt; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::SILVICULTURA::PROTECAO FLORESTAL

This study deals to the morphology of the "four-spotted beetle", Metaxyonycha angusta, and to evaluate the effect of tree damage by beetle cloned eucalypt tree. Lab works were developed at the Federal university of Viçosa and Embrapa-Forests . Activities were carried out in a eucalypt plantation of cloned in the Andrelândia country, Minas Gerais State, Brazil. In the last case, A randomized experimental 3-blocks desing was used; each experimental unit had 25 trees randomly marked. The diameter and height growth were evaluated up to the 70 th month after trees were planted. As result, we found adult M. angusta has the elytra convex, yellowish, and with four blue-greenish spots. The head is wider than long. Pronotum is convex and more long than wide with scattered punctuation. Abdome with five visible segments both the sexs. The legs are free and develop without modifications in the three parts of the legs. In some variable the growth was presented with harmful alteration while in others the alterations had been compensatory or exactly equal to the one of the not damage trees. Wood losses were then evaluated up to the different defoliation levels caused by leaf-beetles in the first year, and, the highest value was 40.2%, compared to the control production 59.47 m3 /ha of wood was not produced due to the most severe defoliation level. Since this lost wood may be more valuable than the IPM techniques usable against leaf beetles, we consider the M. angusta as a new and additional pest to the Brazilian eucalypt plantations.